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External Beam Radiation Therapy

In external beam
radiation therapy
, a machine called a linear accelerator produces radiation. Short bursts of x-rays are directed from the machine at your cancer. The x-rays come out in a square-shaped manner. The radiation oncologist designs special blocks or uses special columnators within the machine to shape the radiation beam so that it treats the cancer and as little normal tissue as possible.
Newer techniques, such as conformal therapy and intensity modulated treatment (IMRT) may be used to help deliver as precise and controlled a dose to the tumor area as possible. In general, radiation for non-Hodgkins lymphoma will involve treating the areas involved with the lymphoma.

Like
chemotherapy
, the side effects from radiation result from injury to the normal tissue. There are many ways that the radiation oncologist can customize your treatment to try to kill as much cancer while sparing as much normal tissue as possible. The radiation oncologist will determine how many treatments you will receive. Sometimes they will be once a day and sometimes twice a day. Each treatment generally only takes a few minutes. The total treatment time can range from 5-8 weeks depending on the total dose required.

Radiation therapy can be given to treat cancer at its initial site or when it has spread. In some cases, once cancer has spread, radiation is no longer curative. However, the treatments can help resolve problems that the cancer may be causing, including local pain and weakness.

Many people believe that when you have received a certain dose of radiation you can no longer get any more treatment. It is true that each tissue in the body can only safely tolerate a certain dose of radiation. However, the therapy is very focused, and it is possible that you can get additional treatments to an already treated area or certainly to an area not yet treated. Ask your radiation oncologist about what dose you can safely receive.

When to Contact Your Doctor

Call your doctor if:

You develop side effects from the treatment

You develop new or unusual symptoms

Your skin is red, blistered, or swollen

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.